| Keywords |
Daylight dimming; Control option; Photosensor; Lighting energy; Prediction models |
| Abstract |
This study analyzes the system performance of daylight dimming controls for a small office in Shanghai to suggest appropriate control options. A series of simulations for diverse daylight conditions were conducted using ReLux and consecutive computations were employed. For north-facing conditions, partiallyshielded photosensors used with horizontal blinds in June, 45° blinds in March as well as June, and no blinds in December functioned successfully. Lighting energy savings by them ranged from 35.5 to 47.9%. The horizontal and 45° blinds in December failed to achieve a target illuminance. Unshielded-photosensors used with horizontal blinds in June and no blinds in March and June provided successful controls with lighting energy savings from 78.3 to 90%. For south-facing conditions, partially-shielded photosensors combined with horizontal and no blinds in December achieved successful controls with lighting energy savings of 74.0 and 75.3%, respectively.
Except them, all daylight conditions overshot a target illuminance. Unshielded-photosensors with horizontal and no blinds functioned successfully with lighting energy savings from 84.4 to 90%. These photosensors used with 45° blinds undershot a target illuminance. Prediction models between desktop and photosensor illuminance levels were acceptable with a significance level of 0.05 and strong linear correlations existed between them. |